Although the idea of applying connectors at the factory or in the field that could simply be plugged into mating connectors on an adjacent length after installation has been considered for some time, it is only recently that it has been considered practical. Wire joining is a very time consuming operation, and when done, for example, in a manhole, under an aerial tent, or in a pit for buried cable, it is performed under adverse conditions. Splicing, accordingly, is relatively slow, and errors are commonly made which must be corrected later, or the wires remain unusable.
Presently available preconnectorization devices are bulky, and therefore limited in utility. Specifically, presently available preconnectorized ends cannot pass through any type of reel opening or small duct as is the standard practice for other cables. When a large pair cable is preconnectorized, the outside diameter of the cable is substantially increased as a result of the connector being added to the dimensional limits of the cable. As a result, preconnectorizing of both ends of the cable is currently practiced in aerial and direct buried plant, but not in the underground where manholes and duct runs are common.
As population grows and greater numbers of communication lines are desired, large pair cable will be increasingly used. Further, when cable is to be pulled through underground ducts and connected at common locations such as manholes, the situation becomes further complicated. When the ducting leading to the manholes was orginially built in the past, typically, no thought was given to use of large pair cable or preconnectorization. In the typical case the standard duct has an inside diameter of only four inches. The standard large pair cable (e.g. 3600 pair cable) has an outer diameter of 3.55 inches. As discussed previously, a pulling means is fitted around the cable to pull the cable through the duct. There must be sufficient clearance between the cable with pulling means attached and the inside of the duct in order to pull the cable to a manhole for connection to another preconnectorized cable. In terms of presently available preconnectorization devices, this means that pulling a standard large pair cable through a standard duct is impractical. However, applicants have discovered a method for organizing a preconnectorized cable utilizing applicants' unique connector which does not increase the outer diameter of the cable, thereby allowing it to be pulled through a standard duct.
The applicants have discovered apparatus for preconnectorizing cable core wires in a simple, rapid and effective manner, resulting in a neat and compact assembly, which is easily traced and tested. Stripping of insulation and soldering of wire ends is avoided and a minimum of space is required.
The standard cable comprises a core of wires and a sheath covering and protecting the core. The core is divided in binder groups of wires. As is standard in preconnectorization art, the sheath is stripped back a predetermined distance from the end of the cable. Normally, the sheath is stripped back a little more than twice the expected splice length since matched ends of cables will be joined by folding back before splicing together. The binder groups are divided into banks and are preconnectorized.
As will be appreciated by those skilled in the art, a maximum splice length cannot be exceeded for a given manhole. Hence, not only must a cable be of a maximum outer diameter after preconnectorization, but also the distance wherein the sheath is pulled back, the binder groups divided into banks and the cable preconnectorized, is limited by the splice length possible. Typically, the maximum number of banks possibly assuming standard length is two.
Upon the above recognition the applicants discovered a method for dividing the binder groups into the maximum number of partial banks and selecting the maximum number of binder groups to be in each partial bundle.
Given the maximum number of full banks to be two, applicants divide each cable end into four quarter banks after stripping back the sheath approximately twice the splice length. Each quarter bank containing a preselected number of binder groups is then attached to a uniquely designed wire organizer which does not exceed dimensional limitations discussed more fully below. The binder groups of each quarter-bank are then bundled to the successively diminishing core.
A key element in the success of the method is applicants' connector consisting of three major parts: first and second wire organizers and a contact element means. The wire organizers are of a form factor sufficiently small and are organized such as to fit around the cable core radially and axially without increasing the outside composite diameter of the cable. The wire organizers are attached to corresponding core wires in cables to be connected. The cables may then be pulled through the ducts and then may be later connected electrically by the separate contact element means. The instant invention further includes unique devices connected to the preconnectorized cable for pulling said cable through standard ducts.